The women's world number nine was adjudged to have marked her ball on the 17th an inch away from where she picked it up.

The mistake was flagged by a TV viewer who emailed the LPGA to alert them to the rule violation.

Mickelson said discrepancies over marking the ball were an issue on the men's tour.

"I know a number of guys on tour that are loose with how they mark the ball and have not been called on it," he said.

"I mean, they will move the ball two, three inches in front of their mark, and this is an intentional way to get it out of any type of impression and so forth and I think that kind of stuff needs to stop."

The three time Masters winner also defended Thompson, saying, “I think that she should be given the trophy” and that the issue could have been dealt with a warning rather than a penalty.